1. Field of the Invention
The present invention relates to a technology for allocating tasks to nodes in a distributed processing system comprising plural nodes each having at least one processor.
2. Description of the Related Art
In order to execute an application in a distributed processing system comprising plural nodes each having at least one processor, a determination should be made as to which node should be used to execute an application task. One problem encountered in this process is how to maintain consistency in computation, which is so important that an outcome of an event may affect all nodes. Conventionally, there has been known a method whereby consistency between nodes is maintained by communicating events between nodes or a method whereby consistency between nodes is maintained by allowing a representative node to serve as a dedicated server so that an important task is executed only in the representative node.
According to the first method, results of arithmetic operations in the nodes may differ so that consistency is lost. In the second method, non-representative nodes are connected to the representative node serving as a dedicated server. Therefore, it is difficult to switch to a different node to cause it to represent the nodes, or to add a new node while the application is being executed.